It is bad news for anyone living near to a busy road – the sound of traffic is likely to scare birds away from your garden.

Scientists have found that the noise created by passing traffic causes birds to actively avoid areas afflicted by the sound.

They created a “phantom road” in the middle of an area of roadless countryside by playing traffic noise over a set of speakers.

They found that the abundance of birds in the area declined by more than a quarter. Two species avoided the areas where the sounds were played altogether.

The scientists, who are based at Boise State University in Idaho, believe the noise of roads may drive birds away because it makes it harder for them to listen for predators and can mask their own songs.

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Dr Christopher McClure, a biologist at Boise State University who led the research, said: “Our results demonstrate that noise alone is enough to cause some birds to avoid a site — suggesting that road noise might be, in some instances, the main driver of the effects of roads on animals.

“Migrating birds might strongly avoid noise because of their inherent mobility — they can easily avoid a noisy site, given there are other suitable, quieter areas nearby.

“We substantially depleted the population of migratory birds and caused entire species to almost completely avoid an otherwise high-quality stopover site using only traffic noise — demonstrating that anthropogenic noise can alter the amount of habitat available to migratory birds during stopover.”

The birds most affected by the noise include the yellow warbler and cedar waxwing, which both avoided the site entirely, two species of sparrow and dark eyed Junco.

It is likely roads would have similar impacts on birds in other parts of the world, including the UK. Previous research has found that many birds change their songs when living in noisy environments like towns and cities.

Dr McClure and his colleagues said the impact of road noise could mean birds are unable to use otherwise suitable habitat because they are too loud.

Dr McClure added: “Because 83% of the USA is within 1km (0.6 miles) of a road, it is likely that noise-sensitive species such as the Yellow Warbler avoid substantial areas of otherwise suitable habitat simply because they are too loud.

“Although our results demonstrate that traffic noise can severely affect bird abundances, other effects of roads will likely add to or multiply the effects of noise.”